Program clock



Jan. 24, 1950 L. Y. LASSITER PROGRAM CLOCK 5 Sheets-Sheet 1 Filed Oct. 15, 1944 Jan. 24, 1950' Y. LASSITER 2,495,462

PROGRAM CLOCK Filed Oct. 13,1944 5 Sheets-Sheet 2 Q36 74 no 75 86 @85 Leon Y. Lassn'ez.

- amzg Jan. 24, 1950 .5 Sheets-Sheet 3 Filed Oct. 13, 1944 4 fi/ A) ,H W M W v u M m a a 1, J m 0 3 m Z 3 u u u g N m m w/ l a Z i huum E fHEE m I r .v a 6 j I .9 h al p Jan. 24, 1950 L. Y. LASSITER PROGRAM CLOCK 5 Sheets-Sheet 5 LEON Y. Lassn'en,

Filed Oct. 13, 194

W qlw MA l h 1 @IllrlL 2w m 0 Z95 0 ,21% L 9 .8 P ,FIE. M M 8 4 w W m M m U no 0 K I/ w Patented Jan. 24, 1950 PROGRAM CLOCK Leon Y. Lassiter, Columbia, Mo. Application October 13, 1944, Serial No. 558,573

3 Claims.

This invention relates to improvements in pro- '7 gram clocks for use in schools, factories and such places where it is desired to have signals sounded or given at regular and predetermined intervals.

The primary object of the invention is to provide an apparatus of this nature which is simple, efflcient and positive in operation and which has a wide range of adjustment such that it may be set up to give signals at intervals of as little as one minute, and On any selected days of the stopping the driving mechanism, and means for manually sounding the signals independently of j the time settings for the automatic operation thereof.

Still another object is to provide a convenient and attractive cabinet or housing in which the program clock and associated mechanism may beconcealed but in such manner as to provide for convenient access thereto for adjustments, and with a time or regular clock exposed to view and synchronized with the program clock. I'he housing also provides exposed switches for sounding the signals manually.

Still a further object is to provide a program clock structure embodying as its driving motor a synchronous electric clock unit permitting the program of signals to be accurately synchronized with the regular electric clocks of the school or other location in which the mechanism is installed.

Other and ancillary objects of the invention will be made apparent in the course of the following detailed specification, reference being had therein to the accompanying drawings wherein:

Figure 1 is a frontal elevation ofthe program clock, showing the same as built'on a panel forming a part of the rear section of the cabinet or housing.

Figure 2 is an enlarged detail View of a fragment of the program chain' used in my structure. Figure 3 is a frontal elevation of the housing showing the time clock disposed in the front section thereof, and showing the program clock panel partially broken out to disclose parts of the program clock mounted behind the same.

Figure 4' is a side or edge view of the housing with an upper part of the rear wall broken out to disclose the interior mechanism.

Figure 5 is a side view of a lower part of the housing and the tubular shield for the program chain, with parts broken away to show interior arrangements.

Figure 6 is a view similar to Figure 1 but showing a modification of the clock structure using a shorter chain and adapted to give signals at intervals of five minutes, or multiples thereof.

Figure '7 is a fragmentary rear elevation of the panel of the clock of Figure 6 and of parts of the mechanism mounted thereon.

Figure 8 is a wiring diagram of the program clock and associated elements.

Referring now more particularly and by reference characters to the drawings, my program clock apparatus, as shown in Figures 1 through 5, is built in a cabinet or housing having a rear section It! adapted to be secured to a wall H, or other support, and a front section [2 hinged to the rear as at it and with a clasp and lock device M for holding said front section closed over and against the rear. Both sections have substantial depth defined by walls and upper and lower ends as clearly shown, and the open front of the rear section is closed by a panel or mounting plate l5 releasably secured in place by the screws It. This panel It supports practically all of the parts of the program clock, as will now be described, and makes installation of the apparatus in any type of cabinet very convenient.

The driving motor for the clock is a synchronous electric unit 11 secured by its base 3 to the rear of the panel 15 and arranged with its hour hand spindle 19, minute hand spindle 20, and sweep second hand shaft 2| extending through the panel to the front thereof. A dial 22 is provided on the front of the panel centered about the axes of these shafts to facilitate the proper setting of the mechanism and a sweep second hand 23 is provided at the extremity of the shaft 2| to make such settings accurate.

As here shown two driving sprockets 24 and 25 are secured, one in front of the other, on the minute hand spindle 29 and each has sixty teeth around its periphery adapted to engage a linked program chain trained thereover. One of such chains is herein shown and designated at 26, and both are duplicates insofar as their construction and arrangement is concernedf Each chain has seven hundred and twenty links, corresponding to the number of minutes in a twelve hour period, and they are accordingly of considerable length. To accommodate this length I provide near the lower edge of the panel l5 a spaced pair of double grooved, flanged pulleys 2!-28 journaled upon pins 29 and the chains, hanging from the driving sprockets, are passed down over inner sides of these pulleys and, thus having their side portions brought into proximitypthey drop into the iopen upper end of a tubular'shield member 38 (Figure 5) which extends into the housing in the proper position for this purpose. The shield memberis supported at its upper ends by screws iii "in aa bracket 32 which is secured as shown to the lower end of the housing section I and'whichhas'a flange 32a secured to the wall at! to .:support the housing therefrom. The lower end of the shield member 3!! is receivedin the eye 33 of ascrew $4 fastened in the wall and holds the shield periiectly vertical. Two .aidler "sprockets --3 -=3B 'are disposed near thelowerrendzof the-shield 1 member and the lower bight :portions :of the chains are :trained thereover.(Figure-5L and the chainsare 1711115 seen to 'be whollyenclosed while being free to advance as the-driVingsprccketsFZA-Hrotate. The .idler sprockets ;35-'35 are carried upon a rbaseplate fi'i securedrbyn screw 38 to the'inner asidexof the *shield membereand the-baseplate has =contact :leaf 43 :and upper contact .leaf '44 while the other has corresponding .lower and upper .leaves 45 and-450i similariorm. .These leaves of the switches are-mounted upon the bracket- 41 secured to-the .face of lth panel. and allare insulatedirom each-other, and from-the bracket, by conventionally arranged insulation represented generally at 48. LDisposed "beneath the .lower leaves i3--A5 of thcswitches are wear-strips .or "spring :leaves 48 which :haveccarn :blocks 5! .on their undersides iadapted normally to .just clear the program cchains "where they *pass over the driving sprockets. :An insulating bushing 51 .in the panel 15 immediately .-at the .ends of the switches permittheleadstherefrom to becarried back behind-the-panel as clearly shown.

:For cooperation with the circuit control :switches illzjlprovide the program chains with signal clips, bestshowniin-Figure :2, designated generally at 52 which take the form of extra links .like :thoseused in 'the chains themselves which extra links, when slightly spread, :may beclipped over :anyione of thelinks andawill then tightly engage the same to"stay.in place on *thecnains. These flips-52 will .then proiect,as represented at 53, :beyond .the outer "surface .Of "the :chains andhence will, they. reach the said switches, engage the cam blocks 50'to urge Tthe lower switch leaves 13, or 45,-upwardly into contact with the upper leaves 44, or 46, thus closing the switches. Every link of the chains may be used to support the signal clips, instead of every other link as in prior devices, thus reducing the necessary length of the chains by one half.

Obviously the driving sprockets 24-25 will make one complete revolution per hour and, having sixty teeth, will accordingly advance the chains a distance equal to one link each minute. This being true it follows that the positions of the signal clips 52 on the various links of the chains will control the times at which the switches ll-42 will be closed, it being possible to close these switches at intervals of as little as one minute apart, or at longer'intervals which are multiples of 'one'minute. Thus ifit isdesired to give signals at fifteen minute intervals the clips 52 will be disposed on every fifteenth link and the ssequence of signals will keep up for twelve hours and be then repeated. The intervals between signals "may, of course, vary as required and to .facilitate counting oil? the links from the starting point, in settingup the program initially, the iliirks corresponding to fifteen minute intervals or other arbitrary number) may be distinctively colored, .as .represented..by .the black .links .54, to istandtoutircm .the .rest of .thechain.

Inasmuch as inmost installations .signals will be irequired only during .one twelve hour ,period .ofsthe day,as.-for exampleifrom six..in ,the mornking -.until. six in i the evening, .and .only on certain -.daysinf .the -.week,.l.provide what I terma calencdar switch mechanism liar-disabling the signal circuits or ,preselec'te'd periods.

Thisiswitch.mechanism comprises'a shaft 55 journaled through the panel l5'loel0w the dial ,22, or .in .any otherrselected-location, .and which .shait {at .the front of 'thepanel .carries a toothed disk 56 cooperating with ,afinger ,5l.secured to and extending .radially .from Lthe hour hand spindle =18. .EachLtimethisfingenpasses .the calendar switch mechanismit will engage onetooth of -.the disk 56 .andadvance the .same a certain increment, .with one such advance movement occurring .once each itwelveihours. In the arrangemerits'hown, this movement of the disk, and its shaft 55, takes place at sixhours on the .clockrlial, bothanteand postmeridian.

.Mounted ion the shaft .55 .behind the panel 15 .is .a .cam disk 58 and the calendar switch .it- :self,.,represented.at 59, .has the normally open .contact leaves-Gland rfil, one of which coacts with La spring .62 havinga .V-shaped tooth 53 iadaptedtoride the periphery of .this'disk. The switchLleavesnre. supportedlby .a bracket .64 -and insulated in usual manner. .So longas the tooth .53 mides the .edge of the cam -disk the leaves ,.B,0- 6I are1pr.%sed into contact (Figure '3) but the .diskhas a series of ..notches 55in its edge .into which the .tootnmayidropdnsequence .as the disk rotates, and each .time 5 this occurs :the .springfiz wilLpermit the switch leaves to .spring apart to open the switch at such time.

ilByiproper spacingandlocation of the-notches :65 according .to .the distance .the .disk 7 moves each time, it 'willrbe apparentthat the switch :58 [may be caused to stand closed iorany .twelve hour pe- :riodand open for :any other, land may :be-caused Ito open .during' the night hours when signals are not or'dinarily required. :Also 'by properly positioning the notches 65 so that the switch'wilhbe npenedfforxseveral sequential positions of ithe'disk =58, zas :shown at .6511, :the :circuits (later .to be :described) may :be fdisabledzfor :full twentyfour :hourrperiods .of selected days.

,5 As herein shown the calendar switch mechanism is arranged to disable the signal circuits 'one half of each day of the week except Saturday and Sunday, on which days the circuits are each of the days on which appear th words 'Off and On indicating the corresponding conditions of the switch. Note that Off occurs twice opposite the sections marked Saturday and Sunday. This set up is suitable for school use but the mechanism may be readily changed for other uses requiring different operating periods by simply changing the disk 58 and dial 55 with others appropriately notched and marked. A

pointer 66a is provided for the dial.

To prevent the driving sprockets 24-25 and other parts from overrunning and to stop the parts in proper positions each time, I provide a click spring 61 secured to a bracket 68 on the panel l and engaging one of the sprockets in a well known manner. A similar spring 69 secured to a bracket 18 engages the toothed disk 5t for a similar purpose.

Disposed behind the panel I5 is a signal switch, or interrupter, designated generally at 1|, again of the normally open leaf contact type having contact leaves 12 and 13 suitably insulated and supported on a bracket 14 secured to the panel. A wear strip 15 is provided and the free ends of these parts extend adjacent to the second hand shaft 2| for actuation by an arm member 16 secured thereto. This arm member 16 extends radially from the shaft and has a finger 11 at its extremity which will engage the wear strip 15 and press the contact leaf 12 toward leaf 13 once each minute. An elongated end 18 of this switch leaf 13 is engaged by a cam 19 of insulating material which is carried on a shaft journaled through the panel. 'By adjusting this off center cam 19 the switch contact leaf 13 may be moved toward or away fromthe other leaf 12 and thus the part of each minute during which the finger 11 will hold the leaves to ether will be varied. Thus the duration of each closed period ofthe switch may be varied and controlled within wide limits and the function of such control will presently appear.

The shaft so forwardly "of the panel has a pointer 8| playing over a scale 82 on the panel and this pointer may be readily adjusted by hand to move the cam and control the switch as described.

A conventional synchronous electric clock 83 is mounted in the front wall 84 of the cabinet or housing and is exposed to view when the front section I2 thereof is closed. Also mounted in this front wall 84 are two conventional push button switches 85 and 85 which, as will presently snap switches 38 and 89 for individually disabling the separate signal circuits without halting the operation of the driving motor 11. The various connections to exterior parts and supply lines are brought out through a conventional outle box 90 on the upper end of the cabinet.

circuit control switch 4i and 42.

Referring now to Figure 8 particularly the wit-- ing of the foregoing parts will be described. Two distinct signal circuits are shown, although more or less of such circuits may be employed by providing an appropriate number of program chains. One circuit has a signal 9 l' and the other a signal 92 which at a common point ar connected to a battery 93 or other suitable source of operating potential, the necessary three leads 94, 95 and 96 then leading to a terminal block 91 disposed in the outlet box 90 previously described. From this terminal block 91 the common lead 98 for both circuits leads to the push button'switches 85 and 66 and the wires 99 and I09 from the separate signals lead to the other terminals of these switches. Obviously then by pressing either push button switch 85 or 86 the corresponding switches may be actuated at any time and independently of the time control.

Also from the common lead 98 a wire 10! leads to one terminal of the signal switch 1| and the other terminal of this switch'is in turn connected by wire I02 to one terminal of the calendar switch 59. The other terminal of this switch is then connected by wires I03 to one terminal of each The other terminals of these switches'are separately connecteol by leads Hi l and to the switches'88 and 89 respectively which are in turn connected thence by wires I96 and I01 to the signal circuit leads 99 and I90. The switches 59 and "are thus seen to be series connected with both circuit control switches 4| and 42 and'to complete either signal circuit requires the closing of three distinct switches.

The supply for the driving motor I1 is connected to a terminal blockHJB and thence to the terminal unit I09 of themotor by wires H0 and H l. The master switch 81 is in one side of this supply circuit so that the motor may be stopped at any time. The clock 83 "is connected across a terminal block H2 which is connected by wires H3 and H4 to'the supply terminals at I08 and in such manner that the master switch 81 will have no control over the clock.

A tap lead H5 is connected to the controlled side of the signal switch 1| and to a terminal point H5 for conveniently connecting another program clock into the circuits and controlling the signals thereby. Such clocks of the single action magnetic type which advance one minute each time they are energized would be connected in parallel between the'terminal point l6 and the common connection between the signals 9 l92 as will be understood.

It is believed that the operation will be understood from the foregoing without extended description at this point. Obviously the driving motor l1 and electric clock 83 will o'peratein accurate synchronism, without mechanical-connections of any kind, and the signal clips 52 being properly placed on the program chains will cause the signals to be sounded exactly at the desired and predetermined times. The sweep second hand 23 facilitates the initial synchronization of the program clock with the clock 8 3and, once the driving sprockets and program chains are properly arranged tobring one of the'sign'a l clips under the circuit control switches 4l,-4 2 exactly on the minute, accuracy/of all signal intervals will be insured. v 5' Inasmuch as the calendar switch 59 and signal switch 1! are series connected with each other, and the circuit control switches 4l-42, both switches 59- 1! must be closed before "the closing of; switches M will complete the signal cirwits. This being true the circuits will not be act-hated unless the calendar switch mechanism propercond-ition and the opening and closing of the signal switch. being controlled in duration loy the cam 19. will have absolute control over the duration of each signal sounded by the proera-m clock.

Convenient access to the program clock mechanism may lee had .for setting up the program chains and making other adjustments by opening the .iront section :I'Z oi the cabinet, but this section he looked to prevent such access being obtained by unauthorized persons.

Attention is directed to the important fact that the action of the mechanism is intermittent and that remains stationary-except for a period or approximately three seconds of each minute. For this purpose the eight toothed gear 350. is

provided and the arm member 16 engages this i gear once each minute, advancin the gear one moth -.eacl'i time it :is engaged. Such movement is exactly equal to one minute travel of the minute sprocket .24.. The member I6 engages the gear 15o Just one-half revolution after it closes the signalling point blades 12-43 and provides onehalf m-in-ute synchronization between the advancing action and the signalling action,

Beierrine now more particularly to Figures 6 and 7 of the drawings, it have shown therein a modification of my program clock wherein the signals will be given ordinarily at five minute intervals ormultiples thereof. panel, driving motor and calendar switch mechanism in this clock are exactly as previously described and are, accordingly, indicated by the same reference characters. Only one driving sprocket is required and is indicated at and in distinction to the previous structure this sprocket has twelve studs Ill on its forward surface evenly spaced therearound and corresponding, therefore, to five minute intervals of time. These studs ii? cooperate with a twelve toothed sprocket or ratchet disk I I 8 which is carried on a shaft i it journeled in a bracket I29 on the panel I5, the stu s advancing the sprocket one tooth every five minutes as will-be clearly apparent.

The shaft H9 carries one (or more according Lethe number of signal programs desired) driving sprocket I21 over which is trained the program o chain 122 carrying the signal clips exactly as has been described. This chain being advanced one link every five minutes has only one hundred and forty-four links and is accordingly much shorter than the chains of Figures 1 to 6. It may r:

in fact be wholly contained within the cabinet and runs over two .idlersprockets E23 and I24 JOlimaled on the front of the panel adjacent the lower corners thereof. 'The tubular shield member is not required and the installation is somewhat more compact as a result.

- The sprocket H9 is engaged by a click spring 425 secured to the panel at I25 to prevent it from overrunning.

In this structure the signal switch, indicated generally at I21, has the two contact leaves and 25 supported on the bracket secured to the back of the panel I5 and a wear spring '31 moves the lower leaf I29 to close the switch. This-movement is brought about by means of a lug I32 carried by and radially projecting from a toothed disk I33 which disk is rotated by a suitable geared connection I34 with a part of the gear train of the driving motor mechanism to make one complete revolution every five min- B utes.- Thus'once each five minutes the lug I32 will engage the hump on the wear spring 1.3I and-close the switch, such flve minute intervals corresponding with the intervals at which the 5 program chain closes the circuit switch 42 will be understood and the signal switch thus serving in exactly thezsame capacity as switch H. The upper contact leaf I28 has an extension I3 3 cooperating with the cam 1-9 to control the duration of the signals .as has been described.

The lug 132 is secured to the disk I33 by ID, rew i3! and the disk has several other opens iii; to receive .asimilar :screws for mounting other lugs (not shown) by :means of which signals "be given groups at one minute, or two and one-half minute intervals. In other words, the circuit switch 42 :being held closed for a full :frve .minute period, the lugs on the disk !33 will complete the circuit to the signal either once during the five minute period, as here shown, or twice -,or ffive times in "the-same length of time, :by proper mounting of the lugs.

Attention is called to the dial I39 carried'w the shaft 2:40 on which thedisk I33 is mounted. At one point, corresponding the position in h the lug 5'32 closes the signal switch 421, s dial carnies .on :its forward side the word Set which will be visible through an open- !65 in the panel I5. The program chain is s t up initially only when this word "*Set is in in order that the circuit switch closing will properly synchronized with that of the signal so. in as will be understood.

The driving sprocket 25 in each type of clock may have imprinted thereon, or secured thereto herein shown, an indicating pointer I12 to facilitate proper location :of the sprockets on the minute :hand spindle.

Aside from the foregoing differences in the control over the program of signals by this signal switch EZl the clock shown in Figures 6 and '7 operates exactly the same as that previously ibed and will not, therefore, be set out in ing now fully described my invention, what claim as new and desire to secure by Letters ate. t is:

l. an electric program clock of the kind 'rered to, a vertically elongated housing includfrontal and rear housing members 'hingedly .erted at one side to open laterally apart and to close together at their meeting margins, the two housing members being separated interiorly by means of an instrument panel mounted over frontal side of the rear housing member, an

PU H

"ic' clock unit mounted upwardly upon the inner side of the instrument panel and having hour hand spindle, minute hand spindle and to front thereof, a timing dial on the front of the panel and centered upon the said shafts I'i pass through the dial, a sweep second hand at the outer end of the second hand shaft, of driving sprockets on the minute hand idle inwardly of the second hand, linked prochains trained over said sprockets and depended into the base of the housing, a tubular id in'the housin for enclosing the depended s of the chains, circuit control switches for drive sprockets, signal clips mounted in suitably spaced relation on the program chains and. arranged to co-operate with the circuit control switches in measuring 011 time periods, and a source of electrical energy and suitable wiring and connections for operating the clock.

Y ti

claim 1, a calendar switch mechanism for stopping the clock for pre-selected time periods.

3. In a program clock assembly according to claim 1, the sprocket rotated by the minute hand spindle of the clock unit being arranged to advance one tooth per minute, a signal controlling switch device adjacent the chain and arranged to be actuated by the said signal clips of the chain.

LEON Y. LASSITER.

REFERENCES CITED The following references are of record in the file of this patent:

Number Number 10 UNITED STATES PATENTS Name Date South et a1. Dec. 3, 1901 Lyman June 17, 1902 Honey Aug. 21, 1917 Holt Dec. 39, 1919 Geiger Feb. 10, 1981 Driscoll Aug. 15, 1933 Elliott May 6, 19 11 FOREIGN PATENTS Country Date Germany Aug. 12, 1902 Great Britain Sept, 3, 1925 France June 17, 1920 France July 24, 1925 

